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<FONT color="green">001</FONT>    /*<a name="line.1"></a>
<FONT color="green">002</FONT>     * Licensed to the Apache Software Foundation (ASF) under one or more<a name="line.2"></a>
<FONT color="green">003</FONT>     * contributor license agreements.  See the NOTICE file distributed with<a name="line.3"></a>
<FONT color="green">004</FONT>     * this work for additional information regarding copyright ownership.<a name="line.4"></a>
<FONT color="green">005</FONT>     * The ASF licenses this file to You under the Apache License, Version 2.0<a name="line.5"></a>
<FONT color="green">006</FONT>     * (the "License"); you may not use this file except in compliance with<a name="line.6"></a>
<FONT color="green">007</FONT>     * the License.  You may obtain a copy of the License at<a name="line.7"></a>
<FONT color="green">008</FONT>     *<a name="line.8"></a>
<FONT color="green">009</FONT>     *     http://www.apache.org/licenses/LICENSE-2.0<a name="line.9"></a>
<FONT color="green">010</FONT>     *<a name="line.10"></a>
<FONT color="green">011</FONT>     * Unless required by applicable law or agreed to in writing, software<a name="line.11"></a>
<FONT color="green">012</FONT>     * distributed under the License is distributed on an "AS IS" BASIS,<a name="line.12"></a>
<FONT color="green">013</FONT>     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.<a name="line.13"></a>
<FONT color="green">014</FONT>     * See the License for the specific language governing permissions and<a name="line.14"></a>
<FONT color="green">015</FONT>     * limitations under the License.<a name="line.15"></a>
<FONT color="green">016</FONT>     */<a name="line.16"></a>
<FONT color="green">017</FONT>    <a name="line.17"></a>
<FONT color="green">018</FONT>    package org.apache.commons.configuration.reloading;<a name="line.18"></a>
<FONT color="green">019</FONT>    <a name="line.19"></a>
<FONT color="green">020</FONT>    import java.io.File;<a name="line.20"></a>
<FONT color="green">021</FONT>    import java.net.MalformedURLException;<a name="line.21"></a>
<FONT color="green">022</FONT>    import java.net.URL;<a name="line.22"></a>
<FONT color="green">023</FONT>    <a name="line.23"></a>
<FONT color="green">024</FONT>    import org.apache.commons.configuration.ConfigurationUtils;<a name="line.24"></a>
<FONT color="green">025</FONT>    import org.apache.commons.configuration.FileConfiguration;<a name="line.25"></a>
<FONT color="green">026</FONT>    import org.apache.commons.logging.Log;<a name="line.26"></a>
<FONT color="green">027</FONT>    import org.apache.commons.logging.LogFactory;<a name="line.27"></a>
<FONT color="green">028</FONT>    <a name="line.28"></a>
<FONT color="green">029</FONT>    /**<a name="line.29"></a>
<FONT color="green">030</FONT>     * &lt;p&gt;A reloading strategy that will reload the configuration every time its<a name="line.30"></a>
<FONT color="green">031</FONT>     * underlying file is changed.&lt;/p&gt;<a name="line.31"></a>
<FONT color="green">032</FONT>     * &lt;p&gt;This reloading strategy does not actively monitor a configuration file,<a name="line.32"></a>
<FONT color="green">033</FONT>     * but is triggered by its associated configuration whenever properties are<a name="line.33"></a>
<FONT color="green">034</FONT>     * accessed. It then checks the configuration file's last modification date<a name="line.34"></a>
<FONT color="green">035</FONT>     * and causes a reload if this has changed.&lt;/p&gt;<a name="line.35"></a>
<FONT color="green">036</FONT>     * &lt;p&gt;To avoid permanent disc access on successive property lookups a refresh<a name="line.36"></a>
<FONT color="green">037</FONT>     * delay can be specified. This has the effect that the configuration file's<a name="line.37"></a>
<FONT color="green">038</FONT>     * last modification date is only checked once in this delay period. The default<a name="line.38"></a>
<FONT color="green">039</FONT>     * value for this refresh delay is 5 seconds.&lt;/p&gt;<a name="line.39"></a>
<FONT color="green">040</FONT>     * &lt;p&gt;This strategy only works with FileConfiguration instances.&lt;/p&gt;<a name="line.40"></a>
<FONT color="green">041</FONT>     *<a name="line.41"></a>
<FONT color="green">042</FONT>     * @author Emmanuel Bourg<a name="line.42"></a>
<FONT color="green">043</FONT>     * @version $Id: FileChangedReloadingStrategy.java 1210646 2011-12-05 21:25:01Z oheger $<a name="line.43"></a>
<FONT color="green">044</FONT>     * @since 1.1<a name="line.44"></a>
<FONT color="green">045</FONT>     */<a name="line.45"></a>
<FONT color="green">046</FONT>    public class FileChangedReloadingStrategy implements ReloadingStrategy<a name="line.46"></a>
<FONT color="green">047</FONT>    {<a name="line.47"></a>
<FONT color="green">048</FONT>        /** Constant for the jar URL protocol.*/<a name="line.48"></a>
<FONT color="green">049</FONT>        private static final String JAR_PROTOCOL = "jar";<a name="line.49"></a>
<FONT color="green">050</FONT>    <a name="line.50"></a>
<FONT color="green">051</FONT>        /** Constant for the default refresh delay.*/<a name="line.51"></a>
<FONT color="green">052</FONT>        private static final int DEFAULT_REFRESH_DELAY = 5000;<a name="line.52"></a>
<FONT color="green">053</FONT>    <a name="line.53"></a>
<FONT color="green">054</FONT>        /** Stores a reference to the configuration to be monitored.*/<a name="line.54"></a>
<FONT color="green">055</FONT>        protected FileConfiguration configuration;<a name="line.55"></a>
<FONT color="green">056</FONT>    <a name="line.56"></a>
<FONT color="green">057</FONT>        /** The last time the configuration file was modified. */<a name="line.57"></a>
<FONT color="green">058</FONT>        protected long lastModified;<a name="line.58"></a>
<FONT color="green">059</FONT>    <a name="line.59"></a>
<FONT color="green">060</FONT>        /** The last time the file was checked for changes. */<a name="line.60"></a>
<FONT color="green">061</FONT>        protected long lastChecked;<a name="line.61"></a>
<FONT color="green">062</FONT>    <a name="line.62"></a>
<FONT color="green">063</FONT>        /** The minimum delay in milliseconds between checks. */<a name="line.63"></a>
<FONT color="green">064</FONT>        protected long refreshDelay = DEFAULT_REFRESH_DELAY;<a name="line.64"></a>
<FONT color="green">065</FONT>    <a name="line.65"></a>
<FONT color="green">066</FONT>        /** A flag whether a reload is required.*/<a name="line.66"></a>
<FONT color="green">067</FONT>        private boolean reloading;<a name="line.67"></a>
<FONT color="green">068</FONT>    <a name="line.68"></a>
<FONT color="green">069</FONT>        /** The Log to use for diagnostic messages */<a name="line.69"></a>
<FONT color="green">070</FONT>        private Log logger = LogFactory.getLog(FileChangedReloadingStrategy.class);<a name="line.70"></a>
<FONT color="green">071</FONT>    <a name="line.71"></a>
<FONT color="green">072</FONT>        public void setConfiguration(FileConfiguration configuration)<a name="line.72"></a>
<FONT color="green">073</FONT>        {<a name="line.73"></a>
<FONT color="green">074</FONT>            this.configuration = configuration;<a name="line.74"></a>
<FONT color="green">075</FONT>        }<a name="line.75"></a>
<FONT color="green">076</FONT>    <a name="line.76"></a>
<FONT color="green">077</FONT>        public void init()<a name="line.77"></a>
<FONT color="green">078</FONT>        {<a name="line.78"></a>
<FONT color="green">079</FONT>            updateLastModified();<a name="line.79"></a>
<FONT color="green">080</FONT>        }<a name="line.80"></a>
<FONT color="green">081</FONT>    <a name="line.81"></a>
<FONT color="green">082</FONT>        public boolean reloadingRequired()<a name="line.82"></a>
<FONT color="green">083</FONT>        {<a name="line.83"></a>
<FONT color="green">084</FONT>            if (!reloading)<a name="line.84"></a>
<FONT color="green">085</FONT>            {<a name="line.85"></a>
<FONT color="green">086</FONT>                long now = System.currentTimeMillis();<a name="line.86"></a>
<FONT color="green">087</FONT>    <a name="line.87"></a>
<FONT color="green">088</FONT>                if (now &gt; lastChecked + refreshDelay)<a name="line.88"></a>
<FONT color="green">089</FONT>                {<a name="line.89"></a>
<FONT color="green">090</FONT>                    lastChecked = now;<a name="line.90"></a>
<FONT color="green">091</FONT>                    if (hasChanged())<a name="line.91"></a>
<FONT color="green">092</FONT>                    {<a name="line.92"></a>
<FONT color="green">093</FONT>                        if (logger.isDebugEnabled())<a name="line.93"></a>
<FONT color="green">094</FONT>                        {<a name="line.94"></a>
<FONT color="green">095</FONT>                            logger.debug("File change detected: " + getName());<a name="line.95"></a>
<FONT color="green">096</FONT>                        }<a name="line.96"></a>
<FONT color="green">097</FONT>                        reloading = true;<a name="line.97"></a>
<FONT color="green">098</FONT>                    }<a name="line.98"></a>
<FONT color="green">099</FONT>                }<a name="line.99"></a>
<FONT color="green">100</FONT>            }<a name="line.100"></a>
<FONT color="green">101</FONT>    <a name="line.101"></a>
<FONT color="green">102</FONT>            return reloading;<a name="line.102"></a>
<FONT color="green">103</FONT>        }<a name="line.103"></a>
<FONT color="green">104</FONT>    <a name="line.104"></a>
<FONT color="green">105</FONT>        public void reloadingPerformed()<a name="line.105"></a>
<FONT color="green">106</FONT>        {<a name="line.106"></a>
<FONT color="green">107</FONT>            updateLastModified();<a name="line.107"></a>
<FONT color="green">108</FONT>        }<a name="line.108"></a>
<FONT color="green">109</FONT>    <a name="line.109"></a>
<FONT color="green">110</FONT>        /**<a name="line.110"></a>
<FONT color="green">111</FONT>         * Return the minimal time in milliseconds between two reloadings.<a name="line.111"></a>
<FONT color="green">112</FONT>         *<a name="line.112"></a>
<FONT color="green">113</FONT>         * @return the refresh delay (in milliseconds)<a name="line.113"></a>
<FONT color="green">114</FONT>         */<a name="line.114"></a>
<FONT color="green">115</FONT>        public long getRefreshDelay()<a name="line.115"></a>
<FONT color="green">116</FONT>        {<a name="line.116"></a>
<FONT color="green">117</FONT>            return refreshDelay;<a name="line.117"></a>
<FONT color="green">118</FONT>        }<a name="line.118"></a>
<FONT color="green">119</FONT>    <a name="line.119"></a>
<FONT color="green">120</FONT>        /**<a name="line.120"></a>
<FONT color="green">121</FONT>         * Set the minimal time between two reloadings.<a name="line.121"></a>
<FONT color="green">122</FONT>         *<a name="line.122"></a>
<FONT color="green">123</FONT>         * @param refreshDelay refresh delay in milliseconds<a name="line.123"></a>
<FONT color="green">124</FONT>         */<a name="line.124"></a>
<FONT color="green">125</FONT>        public void setRefreshDelay(long refreshDelay)<a name="line.125"></a>
<FONT color="green">126</FONT>        {<a name="line.126"></a>
<FONT color="green">127</FONT>            this.refreshDelay = refreshDelay;<a name="line.127"></a>
<FONT color="green">128</FONT>        }<a name="line.128"></a>
<FONT color="green">129</FONT>    <a name="line.129"></a>
<FONT color="green">130</FONT>        /**<a name="line.130"></a>
<FONT color="green">131</FONT>         * Update the last modified time.<a name="line.131"></a>
<FONT color="green">132</FONT>         */<a name="line.132"></a>
<FONT color="green">133</FONT>        protected void updateLastModified()<a name="line.133"></a>
<FONT color="green">134</FONT>        {<a name="line.134"></a>
<FONT color="green">135</FONT>            File file = getFile();<a name="line.135"></a>
<FONT color="green">136</FONT>            if (file != null)<a name="line.136"></a>
<FONT color="green">137</FONT>            {<a name="line.137"></a>
<FONT color="green">138</FONT>                lastModified = file.lastModified();<a name="line.138"></a>
<FONT color="green">139</FONT>            }<a name="line.139"></a>
<FONT color="green">140</FONT>            reloading = false;<a name="line.140"></a>
<FONT color="green">141</FONT>        }<a name="line.141"></a>
<FONT color="green">142</FONT>    <a name="line.142"></a>
<FONT color="green">143</FONT>        /**<a name="line.143"></a>
<FONT color="green">144</FONT>         * Check if the configuration has changed since the last time it was loaded.<a name="line.144"></a>
<FONT color="green">145</FONT>         *<a name="line.145"></a>
<FONT color="green">146</FONT>         * @return a flag whether the configuration has changed<a name="line.146"></a>
<FONT color="green">147</FONT>         */<a name="line.147"></a>
<FONT color="green">148</FONT>        protected boolean hasChanged()<a name="line.148"></a>
<FONT color="green">149</FONT>        {<a name="line.149"></a>
<FONT color="green">150</FONT>            File file = getFile();<a name="line.150"></a>
<FONT color="green">151</FONT>            if (file == null || !file.exists())<a name="line.151"></a>
<FONT color="green">152</FONT>            {<a name="line.152"></a>
<FONT color="green">153</FONT>                if (logger.isWarnEnabled() &amp;&amp; lastModified != 0)<a name="line.153"></a>
<FONT color="green">154</FONT>                {<a name="line.154"></a>
<FONT color="green">155</FONT>                    logger.warn("File was deleted: " + getName(file));<a name="line.155"></a>
<FONT color="green">156</FONT>                    lastModified = 0;<a name="line.156"></a>
<FONT color="green">157</FONT>                }<a name="line.157"></a>
<FONT color="green">158</FONT>                return false;<a name="line.158"></a>
<FONT color="green">159</FONT>            }<a name="line.159"></a>
<FONT color="green">160</FONT>    <a name="line.160"></a>
<FONT color="green">161</FONT>            return file.lastModified() &gt; lastModified;<a name="line.161"></a>
<FONT color="green">162</FONT>        }<a name="line.162"></a>
<FONT color="green">163</FONT>    <a name="line.163"></a>
<FONT color="green">164</FONT>        /**<a name="line.164"></a>
<FONT color="green">165</FONT>         * Returns the file that is monitored by this strategy. Note that the return<a name="line.165"></a>
<FONT color="green">166</FONT>         * value can be &lt;b&gt;null &lt;/b&gt; under some circumstances.<a name="line.166"></a>
<FONT color="green">167</FONT>         *<a name="line.167"></a>
<FONT color="green">168</FONT>         * @return the monitored file<a name="line.168"></a>
<FONT color="green">169</FONT>         */<a name="line.169"></a>
<FONT color="green">170</FONT>        protected File getFile()<a name="line.170"></a>
<FONT color="green">171</FONT>        {<a name="line.171"></a>
<FONT color="green">172</FONT>            return (configuration.getURL() != null) ? fileFromURL(configuration<a name="line.172"></a>
<FONT color="green">173</FONT>                    .getURL()) : configuration.getFile();<a name="line.173"></a>
<FONT color="green">174</FONT>        }<a name="line.174"></a>
<FONT color="green">175</FONT>    <a name="line.175"></a>
<FONT color="green">176</FONT>        /**<a name="line.176"></a>
<FONT color="green">177</FONT>         * Helper method for transforming a URL into a file object. This method<a name="line.177"></a>
<FONT color="green">178</FONT>         * handles file: and jar: URLs.<a name="line.178"></a>
<FONT color="green">179</FONT>         *<a name="line.179"></a>
<FONT color="green">180</FONT>         * @param url the URL to be converted<a name="line.180"></a>
<FONT color="green">181</FONT>         * @return the resulting file or &lt;b&gt;null &lt;/b&gt;<a name="line.181"></a>
<FONT color="green">182</FONT>         */<a name="line.182"></a>
<FONT color="green">183</FONT>        private File fileFromURL(URL url)<a name="line.183"></a>
<FONT color="green">184</FONT>        {<a name="line.184"></a>
<FONT color="green">185</FONT>            if (JAR_PROTOCOL.equals(url.getProtocol()))<a name="line.185"></a>
<FONT color="green">186</FONT>            {<a name="line.186"></a>
<FONT color="green">187</FONT>                String path = url.getPath();<a name="line.187"></a>
<FONT color="green">188</FONT>                try<a name="line.188"></a>
<FONT color="green">189</FONT>                {<a name="line.189"></a>
<FONT color="green">190</FONT>                    return ConfigurationUtils.fileFromURL(new URL(path.substring(0,<a name="line.190"></a>
<FONT color="green">191</FONT>                            path.indexOf('!'))));<a name="line.191"></a>
<FONT color="green">192</FONT>                }<a name="line.192"></a>
<FONT color="green">193</FONT>                catch (MalformedURLException mex)<a name="line.193"></a>
<FONT color="green">194</FONT>                {<a name="line.194"></a>
<FONT color="green">195</FONT>                    return null;<a name="line.195"></a>
<FONT color="green">196</FONT>                }<a name="line.196"></a>
<FONT color="green">197</FONT>            }<a name="line.197"></a>
<FONT color="green">198</FONT>            else<a name="line.198"></a>
<FONT color="green">199</FONT>            {<a name="line.199"></a>
<FONT color="green">200</FONT>                return ConfigurationUtils.fileFromURL(url);<a name="line.200"></a>
<FONT color="green">201</FONT>            }<a name="line.201"></a>
<FONT color="green">202</FONT>        }<a name="line.202"></a>
<FONT color="green">203</FONT>    <a name="line.203"></a>
<FONT color="green">204</FONT>        private String getName()<a name="line.204"></a>
<FONT color="green">205</FONT>        {<a name="line.205"></a>
<FONT color="green">206</FONT>            return getName(getFile());<a name="line.206"></a>
<FONT color="green">207</FONT>        }<a name="line.207"></a>
<FONT color="green">208</FONT>    <a name="line.208"></a>
<FONT color="green">209</FONT>        private String getName(File file)<a name="line.209"></a>
<FONT color="green">210</FONT>        {<a name="line.210"></a>
<FONT color="green">211</FONT>            String name = configuration.getURL().toString();<a name="line.211"></a>
<FONT color="green">212</FONT>            if (name == null)<a name="line.212"></a>
<FONT color="green">213</FONT>            {<a name="line.213"></a>
<FONT color="green">214</FONT>                if (file != null)<a name="line.214"></a>
<FONT color="green">215</FONT>                {<a name="line.215"></a>
<FONT color="green">216</FONT>                    name = file.getAbsolutePath();<a name="line.216"></a>
<FONT color="green">217</FONT>                }<a name="line.217"></a>
<FONT color="green">218</FONT>                else<a name="line.218"></a>
<FONT color="green">219</FONT>                {<a name="line.219"></a>
<FONT color="green">220</FONT>                    name = "base: " + configuration.getBasePath()<a name="line.220"></a>
<FONT color="green">221</FONT>                           + "file: " + configuration.getFileName();<a name="line.221"></a>
<FONT color="green">222</FONT>                }<a name="line.222"></a>
<FONT color="green">223</FONT>            }<a name="line.223"></a>
<FONT color="green">224</FONT>            return name;<a name="line.224"></a>
<FONT color="green">225</FONT>        }<a name="line.225"></a>
<FONT color="green">226</FONT>    }<a name="line.226"></a>




























































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